[PATCH v2 libXi multitouch 4/4] Implement support for XI 2.2

[Peter Hutterer]

On Fri, Oct 14, 2011 at 09:22:27AM -0700, Chase Douglas wrote:
> On 10/13/2011 10:23 PM, Peter Hutterer wrote:
> > From: Chase Douglas <chase.douglas at canonical.com>
> > 
> > XI 2.1 has not been implemented yet, so this code defines version info
> > for it too. These will be dropped when XI 2.1 support is merged.
> > 
> > The code is based on what we have in the prototype libXi in Ubuntu. The
> > main differences are:
> > 
> > * No touch valuator classes
> > * No TouchUpdateUnownedEvents
> > * Addition of raw touch events
> > * Touch grab and ungrab is handled in existing passive grab functions
> > * XIAllowTouchEvents has been added as an extension of XIAllowEvents
> > * XIAllowEvents has been extended when XI 2.2 is supported
> > 
> > The last item causes a bit of an issue. The XIAllowEvents handling in
> > released X.org servers check that the size of the request is exactly the
> > size published in XI 2.0. Since we are extending the request, we must
> > get the right request size from the Xlib buffer depending on what
> > version of XI the server supports.
> > 
> > None of this code has been tested because we don't have a server to test
> > it with yet.
> > 
> > Signed-off-by: Chase Douglas <chase.douglas at canonical.com>
> > Signed-off-by: Peter Hutterer <peter.hutterer at who-t.net>
> > ---
> > Changes to v1:
> > - adjust to current protocol
> > - rebase on current libXi master
> > - re-use code in XIAllowTouchEvents and XIAllowEvents 
> > 
> > This patch requires http://patchwork.freedesktop.org/patch/7580/
> > Untested for lack of a server supporting MT, and it doesn't include the man
> > pages yet either.
> 
> [snip]
> 
> > diff --git a/src/XIAllowEvents.c b/src/XIAllowEvents.c
> > index 1d388b3..e53cf25 100644
> > --- a/src/XIAllowEvents.c
> > +++ b/src/XIAllowEvents.c
> > @@ -29,9 +29,12 @@
> >  #include <X11/extensions/extutil.h>
> >  #include "XIint.h"
> >  
> > -Status
> > -XIAllowEvents(Display *dpy, int deviceid, int event_mode, Time time)
> > +static Status
> > +_XIAllowEvents(Display *dpy, int deviceid, int event_mode, Time time,
> > +                    unsigned int touch_id, Window grab_window)
> >  {
> > +    Bool have_XI22 = False;
> 
> It looks like have_XI22 is set backwards. Shouldn't it be True here, and
> then ...
> 
> > +    int req_len = sz_xXIAllowEventsReq; /* in bytes */
> >      xXIAllowEventsReq *req;
> >  
> >      XExtDisplayInfo *extinfo = XInput_find_display(dpy);
> > @@ -40,14 +43,51 @@ XIAllowEvents(Display *dpy, int deviceid, int event_mode, Time time)
> >      if (_XiCheckExtInit(dpy, XInput_2_0, extinfo) == -1)
> >  	return (NoSuchExtension);
> >  
> > -    GetReq(XIAllowEvents, req);
> > +    /* 2.2's XIAllowEvents is 8 bytes longer than 2.0 */
> > +    if (_XiCheckExtInit(dpy, XInput_2_2, extinfo) == -1) {
> > +        req_len -= 8;
> > +        have_XI22 = True;
> 
> set to False here?

oops. thanks, amended locally.

Cheers,
  Peter

> > +    }
> > +
> > +    GetReqSized(XIAllowEvents, req_len/4, req);
> > +
> >      req->reqType = extinfo->codes->major_opcode;
> >      req->ReqType = X_XIAllowEvents;
> >      req->deviceid = deviceid;
> >      req->mode = event_mode;
> >      req->time = time;
> >  
> > +    if (have_XI22) {
> > +        req->touch_id = touch_id;
> > +        req->grab_window = grab_window;
> > +    }
> > +
> >      UnlockDisplay(dpy);
> >      SyncHandle();
> >      return Success;
> >  }
> 
> BTW, thanks for fixing this up. I was getting close to revisiting this
> patch, but I still wasn't sure exactly how to do it correctly.
> 
> -- Chase